using MongoDB.Driver;
using MongoDB.Entities;

using OpenIddict.Abstractions;

using PrivaPub.Models.User;
using PrivaPub.StaticServices;

namespace PrivaPub.Services
{
	public interface IRootSessions
	{
		Task Revoke(string rootId, CancellationToken token);
		Task End(string rootId, string sessionId, CancellationToken token);
	}

	// Ends everything a root is signed in with: its /clientapi tokens, through a new SessionStamp (checked by JwtEvents),
	// and the Mastodon API tokens and authorizations of each of its personas. Used when its password is changed or
	// recovered, when it signs out everywhere and when it is deleted. End signs out one session only: the device that
	// asked (its Mastodon tokens it revokes itself).
	public class RootSessions : IRootSessions
	{
		readonly DbEntities _dbEntities;
		readonly IOpenIddictTokenManager _tokens;
		readonly IOpenIddictAuthorizationManager _authorizations;
		readonly AuthTokenManager _authTokens;

		public RootSessions(DbEntities dbEntities, IOpenIddictTokenManager tokens, IOpenIddictAuthorizationManager authorizations, AuthTokenManager authTokens)
		{
			_dbEntities = dbEntities;
			_tokens = tokens;
			_authorizations = authorizations;
			_authTokens = authTokens;
		}

		public async Task Revoke(string rootId, CancellationToken token)
		{
			await DB.Default.Update<RootUser>().MatchID(rootId)
				.Modify(u => u.CredentialsChangedAt, DateTime.UtcNow)
				.Modify(u => u.SessionStamp, Guid.NewGuid().ToString("N"))
				.Modify(u => u.EndedSessions, new List<EndedSession>())//the new stamp ends those too
				.ExecuteAsync(token);
			foreach (var link in await _dbEntities.RootToAvatars.Match(ra => ra.RootId == rootId).ExecuteAsync(token))
			{
				await _tokens.RevokeBySubjectAsync(link.AvatarId, token);
				await _authorizations.RevokeBySubjectAsync(link.AvatarId, token);
			}
		}

		// remembered as long as one of its tokens could still be valid; the ones that have expired are forgotten meanwhile
		public async Task End(string rootId, string sessionId, CancellationToken token)
		{
			var now = DateTime.UtcNow;
			await DB.Default.Update<RootUser>().MatchID(rootId)
				.Modify(b => b.PullFilter(u => u.EndedSessions, s => s.Until < now))
				.ExecuteAsync(token);
			await DB.Default.Update<RootUser>().MatchID(rootId)
				.Modify(b => b.Push(u => u.EndedSessions, new EndedSession { Sid = sessionId, Until = now + _authTokens.Lifetime }))
				.ExecuteAsync(token);
		}
	}
}